Irradiation of products, whether they are food products or medical devices, is known in the art. The delivery of a sufficient minimum radiation dose is required to ensure efficacy of the process and compliance with regulations. The ability to maintain the radiation dose below a maximum value is required to avoid damage to the processed product and/or to remain below prescribed regulatory maxima for radiation doses.
Irradiation of products with an irradiation dose that is uniform, to a certain degree, on and within surfaces of a given product is also known. The ratio of maximum dose to minimum dose is referred to as the dose uniformity ratio (DUR). In some prior art uniform dose irradiation systems, steel shutters and an x-ray beam are used to irradiate, one after the other, the surfaces of a product that is conveyed across the x-ray beam multiple times for each of the surfaces. The steel shutters are used to attenuate different widths of the x-ray beam each time the product is conveyed across the x-ray beam in order to obtain a final irradiated product that has received a uniform irradiation dose of x-rays. This is done to achieve a constant DUR for each portion of each surface of the product.
Such prior art systems require multiple passes of the product across the x-ray beam and are inefficient in that they waste a considerable amount of x-ray radiation through the irradiation of the steel shutters during the multiple passes of the product across the x-ray beam.
Therefore, improvements in systems and methods for the irradiation of products are desirable.